OT alert...but that's a weird combination:
/3GB - increase virtual address space in kernel in order to cram more page tables in (NB: exclusively made for huge programs that can and will make use of this by enabling IMAGE_FILE_LARGE_ADDRESS_AWARE flag only)

/PAE is (afaik) only for systems >= 4 GB physical RAM.

Using both switches at the same time does not make much sense whatsoever. Even people who, in terms of experience in servers, have an additional 15 years 'plus' in there (compared to mine) would state that as well. YMMV, though.
(As with all those WPUMs [Windows Power User Myths] there are )